Silicon feedstock material, e.g. doped silicon, is used in photovoltaics for producing solar cells. Most of the silicon feedstock material is doped with boron. However, boron may form together with oxygen a boron-oxygen complex, which may decrease the performance of a solar cell.
A common method for producing doped silicon feedstock material is to add a dopant to molten silicon in a crucible. Possible problems of such methods arise in the margin of error in controlling the quantity of the dopant and thus in the concentration of the dopant in the doped silicon and the distribution of the dopant in the doped silicon.